X300 friends please help!

Symptoms: Tramlining on uneven roads. Car wanders around and sometimes "wrestles" the steering wheel. Its becoming a little scary to drive.

Car: '95 Jaguar XJ6 on 18x8.5 Milans (I know I know ... the objective is to save these wheels) with Michelin Pilot Super Sports 225 50r18.

History: Full suspension refreshed (see list below!)

Suspects:
1) Alignment - tweaked on 3 separate occasions, various toe-ins etc. No help.

2) Upper ball joint - It's the only part i forgot to replace when I did all the suspension work! Took some photos/

3) Tyres too skinny for the 18x8.5 milans?? Perhaps the tyres are a bit stretched and contributes to a stiffer sidewall hence worsening the tramlining. Does this make sense?

4) .... anything else?

------------------------

Anti Roll Bar & Bush Rear
Diagram Part Part No. Qty Comments
1 Rear Anti Roll Bar MNA3500DA 1 Uprated version powerhouseuk; Roll bar bushes to be trimmed to fit
2 Rear Anti Roll Bar Link MNA3505AE 2
3 Bush MNA3504AB 4
4 Plain Washer WC110061J 2
5 Nut NY110041 2
6 Anti roll bar mounting bracket MNA3501AA 2
7 Anti roll bar mounting bush CBC4901 2 To be trimmed
8 Flange head screw JFS11020F 4
9 Bolt C2P7626 2
10 Locking nut FN110041J 2

Anti Roll Bar & Lower Fulcrum Tie
Diagram Part Part No. Qty Comments
3 Anti roll bar bush (comfort) CAC46517 2
7 Anti roll bar link CAC9827 2 Andy's Rose Jointed;

Crossbeam Assembly Front (Original)
Diagram Part Part No. Qty
2 Mounting Bush MNA2370AA 2
3 Vee Mounting (Front Crossbeam) MNC2360AB 2

Frame Carrier Rear (Original)
Diagram Part Part No. Qty
14 Subframe Bush CCC6875 2

Wishbone Assembly Rear (Mod)
Diagram Part Part No. Qty
6 Wishbone Tie MNC2856BA 1
9 Extension bracket MNC2617BA 1
12 Locking Nut JFX11404E 2
13 Bushed Differential Strut MJA3713AD 1
14 Mounting bush (sports) MJA3715AB2 4
15 Flange Head Bolt FB112131 2
16 Spring nut rear suspension JZM100015 2
18 Pendulum Bush (Top) CAC77601 2
19 Pendulum Bush (Bottom) CAC4713 2

Differential Assembly (Mod)
Diagram Part Part No. Qty
2 Tie Stud NNC5715AA 2

Wishbone Hub Assembly Front
Diagram Part Part No. Qty
3 Wishbone Bush Upper CBC5523 4
11 Bush - Front Lower Wishbone MMD1361AA 2
12 Fulcrum Bush Lower CBC2301 2
13 Damper Bush CAC75851 2
15 Balljoint Assembly JLM11860 2

Bilstein Shocks and rear shock mounts, wheel bearings all round

 

The only way I solved the tramlining on my XJR/6 was going to narrower, taller tires. The originals were 255/45x17.

No tramlining with 235/55x17 or 225/60x16

Besides tire size, tire construction and tread design can enter in as well. Experimenting here gets expensive, though !

On another forum an XJR/6 owner recently solved his tramlining problem by merely replacing shocks. He's luckier than most !

Others will chime in.

Cheers
DD

 

Thanks Doug. You're on 17x8's? Did the narrower/taller tyres eliminate tramlining completely or just reduced it?

 

Eliminated completely.

17x8 XJR wheels with the 235/55x17 tires

16x7 XJ6 wheels with the 225/60x16 tires


When I was running the original size 255/45x17 tires the tramlining was startling enough that I wouldn't let my youngest drive the car on the freeway for fear that she'd be caught off guard and over-react. It was downright scary at times. But, even with the 255 tires, different brands/designs made a difference.

Opinions and experiences vary. Lots of archives threads on this subject.

Cheers
DD

 

I'm good on 245/45 x 18 RE003 Potenzas, and a good alignment.

(running later X308 Asteroids)

 

Thanks Al. I believe the asteroids are 8Js? My milans are 8.5J so I'm not sure if the same 245/45 would clear my wells and fender properly. But I think that's definitely on my list. I suspect my current 225s are too narrow, causing the tyre wall to be stretched and unnecessarily stiff.

 

One more question AL NZ, you wouldn't happen to have your alignment settings on your asteroids would you?

 

Yep, same here with the 255s..... so I went with 245/50s as I recall.

Check out the "tramlining" thread here in the forum too, many pages of tire testing and opinions

 

Thank you all.

Think i shall change out the upper ball joints to be safe, and switch to 245/45 r18s

I have seen the other "tramlining thread" but was hoping there'd be new information. I would really appreciate if anyone on 18" wheels could share their alignment settings and their tyre choices!

Best,
kopi

 

 

My local tyre guy fitted up a 235/50x18 Bridgestone on an Asteroid wheel, but it wouldn't clear the inner plastic of the wheel arches when the steering was turned
245/45 is fine however

 

I have a x308, so can't comment on your tram-lining too much, but the 225's are too small for your 8.5J rims.

I 'upgraded' from the standard 225/60R16 to 245/45R18 on 8J front rims (running wider on the rear).

I can confirm that the 245 is about the widest tire you can have (26.6" diameter for both sizes) without rubbing.
Going wider, and you got to reduce the outer tire diameter a bit.
I guess this is the same for both the x300 and the x308.

Further, a 245/45 R18 fills the wheel wells beautifully, without much of a gap to the fender, and is imo better looking than a 255/40.
And you should not have problems to fit this size tires on your 8.5J rims.

On the tram-lining, I should say, that even on a x308, the car became a bit more sensitive.
It is in no way dangerous as described by Doug, but there are situations where you simply feel more forces working the steering wheel.

Lastly, in any of the threads about wide(r) tires, I hardly read anything on the scrub radius.
I do believe this is as important as anything else while going wider, and influencing the tramlining, but seems to be mostly forgotten.
Your Milans are OEM however, and should be OK (ET value some 33?).

 

There are so many things that come into play to cause tramlining......worn shocks,weak springs,old bushings,tire wear/brand/size, and it could be a combination of any of them. Since you replaced most of your bushings you could possibly eliminate that as a factor. I had some serious tramlining going on ( downright dangerous ) with my 95 VDP running the stock 225/60r/16's. They were worn a bit but a simple tire replacement ( Falken brand) and it's almost completely eliminated. I'd still like to see if I can completely eliminate the issue by updating the shocks and maybe replacing the lower a-arm bushings because it looks as if there may be some very slight play in them and the steering rack bushings which will be replaced when I replace my leaking steering rack issue.

 

Thank you all, i think my next course of action is clear.

New tires + upper ball joints it is then. Thank you for the alignment data and the tire size of choice. I will report back if this eliminates the problem.

95leaper, I was wondering about steering rack bushings but read that its not really a serviceable item? My steering rack was refurbished less than a year ago so I i guess it may not be the issue.